Rotary coil compass



ROTARY C011; COMPASS F iied March 11. 1922 2 Sheets-Sheet 1 y 1930. M.M. TITTERINGTQN 1,770,243 I ROTARY CQIL COMPASS Filed March 11. 1922 2Sheets-Sheet 2 f I 1 2a 5 5:

INVENTOR 1 A Tole/my Patented July 8, 1 930 ,oNirEo STATES PATENT OFFICEMORRIS M. TITTERINGTON, OF BROOKLYN, NEW YORK; GEORGE A. TITTERINGTON,EXECUTOB OF SAID MORRIS M. TITTERINGTON, DECEASED, ASSIGNOR TO FIONEERINSTRUMENT COMPANY, INCORPORATED, F BROOKLYN, NEW YORK, A. CORPORA- TIONOF NEW YORK ROTARY COIL COMPASS Application filed March 11, 1922. SerialNo. 542,937.

passes, and more particularly to a new type of rotary coil'compass, orwhat may be referred to as an earth inductor compass which operates bymeasuring or ascertaining the direction of the earths flux.

It is an object of this invention to produce an improved compass whichmore accurately and dependably indicates and points out di rections thancompasses now in use, and which avoids many of the diflicultiesexperienced with ordinary magnetic compasses and with other compasses aswell.

An object of the invention is to provide means for maintaining theproper position of the inductor plane of a compass generator so as tocause a zero indication on-a steering or deviation meter or indicator,such as a. galvanometer, when the vehicle on which the compass is beingused is headed in a compass direction corresponding to the indication ofa course setting controller device and to cause the deviation indicatorto show the direction in which the vehicle is turned off the courseindicated by said course setting controller.

An outstanding object is to improve induc tor compass systems bydevising a novel course setting instrument which I have named a compassdirection controller and which I include as a new element in the compasscombination and by which an operator orients, or sets and resets atwill, the commutator brushes of an inductor generator which is anotherelement of my new combination. My new controller measures the angle ofturn through which the brushes are oriented and directly indicates suchmeasurement in terms of compass direction. Thus my invention includes anew instrument as a novel element in the compass system, and alsocomprises in thereby, the purpose of which is to enable the brushes orarmature to be adjustably oriented, turned or set in azimuth at the willof the operator by use of the new controller. A gear reductiontransmission or one gear thereof or other suitable motion transmittingmeans is included as a part of the brush rotating means by which thecontroller is operatively connected with the generator.

7 --Another important object is to improve the generator inrespect toits stabilization without addition of parts or weight and this isaccomplished by utilizing the armature as a rotor to produce thenecessary gyroscopic force which acts through universally pivotedsupporting means carrying the armature to effect its stabilization, andthus the armature is inherently stabilized. Thus I uti lize the armatureto produce two useful forces to-wit, electric potential and gyroscopicforce. In this way, the weight, size and number of parts composing thegenerator are reduced.

Another object is to produce a compass which gives an indication ofdirection at one or more positions remotely located from the place atwhich the direction of the earths magnetic flux is measured, thuspermitting the measurement of the flux at a position where it is leastdisturbed by iron masses or other local magnetic disturbances. It isalso an object to indicate the direction of the flux at any other placeor places Where it may be of value to know said direction.

While this compass will be found suitable for all navigation purposes,it is particularly useful on aircraft, where the ordinary compass isunsatisfactory in operation due to the movements and inertia of thecraft and to the magnetic effect of the engines which in most cases areclose to the position'where the ordinary compass mu'st bemounted so asto be magnetic flux lines and in obtaining directive indicationstherefrom. The difliculties in generation have been due both to theeffect of the movements of the craft upon which the compass was mountedand to the distortion of the magnetic flux lines by the countermagnetomotive force due to the flow of electric current whileindications were being secured. The solution of the first difliculty hasheretofore been attempted by the stabilization of the generator, butthis involved the addition of complicated or heavy auxiliary apparatuswhich was found objectionable in several particulars, but my inventionaccomplishes this in a practical way with lightweight construction andby omitting additional parts.

In order to successfully overcome the several ditficulties heretoforeencountered, I have produced, among other things, as already suggested,a new electric generator for earth inductor compasses wherein thearmature is itself the gyroscopically stabilizing means and thus thegenerator is inherently stabilized. I have also produced a noveldirection controller which itself includes heading or directionindicating means and by which the generator, particularly the currentcollecting brushes thereof, is adj ustably turned or oriented about anormally vertical axis by which the operator at will and from a distantpoint readily resets the armature brushes to attain for them a positionof null reading on the deviation or steering indicator. I have alsodiscovered that it is not necessary to stabilize the armature itself,provided the brushes be stabilized and so long as the position of thearmature axis be susceptible to control as by carrying the generatorand/or its commutator brushes on rotary mounting means by whichorientation is effected. This I have illustrated as a modification inFigure 8. The principle is the same in either case or form of theinvention, as well as in other forms of construction, and may beexpressed as follows: a

The operation of the compass will be unaffected by movements of thecraft upon which it is carried if the armature of the generator and thecommutator brushes are so related to each other and to the earths field,that the inductor plane of the armature is established or maintainedperpendicular to a plane defined by the armature axis and the directionof the earths flux. By mounting the commutator brushes and/or thearmature axis dirigible in azimuth,.i. e. on the aforesaid rotarymounting means, and by stabilizing the brushes and/or the armature axis,the above relations are maintained established or brought about. Toattain this end is one of the broad purposes of the invention, and forthis purpose I provide a compass controller as a fundamentally newelement for use in inductor compasses to set and establish or maintainthe brushes in proper position and I provide stabilizing means tomaintain the armature or brushes in proper position. The controller isusually manually operated while the stabilization is continuous inperformance and motor driven.

By the inductor pla'ne ofthe armature is meant a plane passing throughthe armature axis and having, for any part-icular generator, a fixedrelation to the brush plane,that is, parallel to the brush plane or tosome definite angle to the brush plane dependin upon the type ofarmature winding, upon the method of connecting the armature-winding) tothe commutator and upon the spacing etween brushes. The brush plane is aplane passing through the brushes and coinciding with or lying parallelto the armature axis. The fixed position of the inductor plane withreference to the brush plane may be determined by moving the brush planeeither by rotating the brushes or by rotating the armature axis or byrotating the brushes and rotating the armature axis until a galvanom"teror other suitable indicator shows zero potential between the brushes.The indnctor plane is then perpendicular to a plane coincident with thearmature axis and lying parallel to the magnetic field.

If the armature be considered as having simple open coil windings, theinductor plane of the armature, is the plane of any winding at theinstant it reaches its mean position in circuit with the commutatorbrushes. If the armature be considered as having a single turn of wireconnected to a single pair of commutator segments of Width equal to: thewidth of the brushes, the inductor plane of the armature is the plane ofthis turn of wire at the instant when the commutator segments andbrushes are in matched position. If the armature be considered as havingany form of winding with any number of turns of wire and any number andwidth of commutator segments, the inductor plane has the samefundamental relation to the brushes as in such single wire form. V v

Obtaining of directive indications from the generated electricpotentials have heretofore involved further difliculties. While someinventors have realized the advantage of using an electric deviationindicator which might give a null reading when the craft is upon thedesired course, all have failed to recognize the advantages of socoordinating the generator and deviation or steering indicator 7 that,there is no current flow when the craft is uponthe desired course. Ihave combined with my new generator, having the beforedescribedcharacteristics and novel features, an electric potential transmissionand indicating system free from the defects of compasses previouslyproposed, together with a compass direction controller, my whole syst egbeing not only theoretically correct but of great practical use uponaircraft and elsewhere.

The accompanying drawinrjs illustrate practical examples of embodimentsof my invention and though there are described preferred forms andoperations, I claim the right of protection as to all changes andmodifications as may properly come within,

the scope and principle of my invention.

. Figure 1 shows a plan view of the inductor generator carried uponrotary mounting means by which the commutator brushes are adapted to beoriented about a normally verforms for adjustably turning the generator.

A fragment of the controller shaft is directed toward the generator andmay be considered as connected with the shaft fragment at the generator.

Figure 3 shows the electric deviation or steering indicator intended tobe connected with the inductor generator.

The first three views therefore show an example of the three instrumentswhich are adapted to be connected together to form a complete inductorcompass system.

Figure l is a side elevation of the generator shown in Figure 1, partsthereof being in section, together with its adjustably turnable mountingmeans carrying the generator and by which particularly the commutatorbrushes are orientedby the direction controller shown in Figure 2.

Figures 5, 6, 7 and 8 show a modified form of the invention.

Figure 5' is a plan view of a generator similarly carried by rotarymounting means by which it is adapted to be adjustably turned about avertical axis, the armature of the generator being mounted horizontally,and its commutator brushes only are stabilized, thus renderingunnecessary, in this form of the invention, the stabilizing of thearmature or the complete generator. Figure 6 shows a plan View of thedirection controller for adjustably turning the generator so that itscommutator brushes and armature are bodily swung or turned about anormally vertical axis.

Figure 7 illustrates an electric potential steering or deviationindicator which is to be electrically connected with the generator shownin Figures 5 and 8.

Figure 8 shows a side elevation of the horizontal type generator ofFigure 5 together with the rotary mounting means therefor which is insection, thisview showing stabilized commutator brushes.

Referring to Figures 1 to 4. to first describe the improvements ininductor generators for the compass system, an armature 51 isjournaledin a gyro or generator frame 52 and in this case the armatureis disposed on a normally vertical axis MM. The frame 52 is suspended ina gimbal ring 53 and'is free to swing about the normally horizontal axispp to permit stabilization of the armature on the vertical axis. issupported-0n pivots 46' carried by brackets 54 and the gimbal is free toswing about an axis Q-Q to contribute to the aforesaid stabilization ofthe armature 51. This con-- struction permits inherent stabilization ofthe generator armature 51 since it produces its own gyroscopic force bywhich to stabilize itself and since the armature is carried by universalpivot means consisting of the frame 52 and gimbal 53. The brackets 54are carried by or upon orientable mounting means in the The gimbal ring53 form of a turntable gear 55 which is in turn carried with astationary installation base or frame 60. The rotary mounting means orgear 55 is adapted to be subjected to an adjustable turning movement ororientation by a compass direction controller.

A vertical journal pin 49 is carried in the base 60 and supports thegenerator on the turntable or base 55 so the generator may be adjustablyturned by a direction controller means to be described, and thisjournalpin 49 preferably contributes to the driving of the generatorarmature by transmitting a power medium through or beyond the pin. Alsothe journal means 49 may act as a center about which slip ring currentcollecting brushes rotate to transmit current from the generator to theelectric potential deviation indicator shown in Figures 3 and 7 to bedescribed. The generator frame or base 60 is adapted to be anchored onthe craft in the installation of the compass system, and thus theinductor generator is mounted on an airplane and stabilized,'and henceits current collecting brushes are stabilized in a horizontal plane.

The generator may be provided with direction indicating means such as acompass dial or graduated circle similar to a direction controllercompass-like dial to be described which facilitates readings andobservations taken from the compass and this dial means is best shown inFigure '1. A lubbers line wheel 56 by a jet 57. Air is obtained from anysuitable source such as an air compressorand is conveyed to the jet 57through a rubber tube 58 from the tubular journal pin 49 through whichcompressed air may be transmitted to drive the generator. Mounted on'the armature shaft is a commutator 59, and for the sake of simplicityonly two armature segments 71 and 72 are shown on the commutator.

Current collecting commutator brus. s 77 and 78 are carried on the gyroframe 52 and bear on the commutator 59.

It is to be understood that this invention is not limited to theparticular form of armature winding or number of brushes shown becausethe drawing shows an elementary and simple form of the apparatus sd asto facilitate an understanding and explanation thereof. Practically anystandard armature winding may be used, and commutator brushes may alsobe adopted from standard practice.

As is well known to those versed in the art, the direction of the earthsmagnetic flux is only horizontal at a few locations on the earthssurface and at most places is inclined at a considerable angle to thehorizontal. An inductor compass, as well as the usual type of magneticcompass, is caused to function by the horizontal component of the earthsflux. The vertical component of the earths flux is largely responsiblefor the erratic action of the ordinary magnetic compass under certainconditions, and co-eliminate the ill efiect of the vertical componentupon the compass of my invention, means are provided to maintain theinductor plane of the generator so as to gain maximum effect of-theearths horizontal flux lines and minimize or eliminate all effects ofthe vertical flux lines.

To the above ends, the entire generator may be stabilized or onlycertain parts thereof are required to be stabilized. It will be shownthat in one modified construction, the

commutator brushes only are stabilized. As K a matter of convenience indesign and construction, the brushes 77 and 78 are parts of a stabilizedgenerator in Figures 1 and 4 and hence are themselves stabilized, butseveral variations are possible in accordance with the principle of myinvention.

Wires 67 are attached to the brushes 77 and 78 and connect withslip-rings 79 and 80. As shown, brush 77 is connected to ring 79,

and brush 78 is connected to ring 80. The

contacts on the slip-rings. are made by brushes 61 and 62. From the sliprings, the wires 67' are run to the electric steering or deviationindicator 47 shown in Figure 3, which may be a galvanometer in whichelectric potential in one direction causes the hand to move to therightof zero, and potential in the other direction causes the hand Thereis an armature coil which is wound around the armature core and has itsends connected to the segments 71 and 72.'

tained by the pilot.

What I call a direction compass controller 45 is shown in Figure 2, andit is used for adjustably turning or orienting the generator and brushmounting) means or gear 55, and hence the generator rushes are orientedinto any desired position about a normally vertical axis at the will ofthe operator who actuates the crank shaft handle 99 of the controller. Acompass dial 44 is carried with, by or on a controller gear 40 and turnstherewith, and there is rovided a lubbers line 63 by which to rea thedirection controller compass-like dial 44. The controller gear 40 isoperatively connected to the generator and brush mounting gear 55through a shaft and manually operable crank :means 99 and gears 39 and43 respectively in such a way that rotation of the gear 40 and of thedirection controller dial 44 through a given angle by means of thecontroller crank, causes corresponding orientation of the generatorbrushes through the same angle about a normally vertical axis.

A navigator at the direction controller handle 99 may therefore from adistance manuall orient the generator brushes about the vertical untilthe direction compass dial 44 shows the desired directon of travel atthe lubbers line 63, at which time the generator brushes 77 and 78 willbe in that required position with respect to the direction of the earthsflux lines as will reduce no potential and hence a null reading on thedeviation indicator 47 when the craft is headed on that direction asshown by the direction controller compass dial 44.

The generator and brush mounting means 55 includes a gear represented bythe same reference 55 and the gear is in mesh with a drive gear 43 bywhich a controller shaft 99' is connected with the generator. The twogears 43 and 55 provide a transmission means or the generator by whichthe rotary brush mounting means is oriented from the controller 45 whichmay be located at a distance from the generator.

The disposition of the various units on an sircraft or other vehicle andtheir practical operation, will now be explained. For the electricalgenerator unit, a location is chosen which is as free as possible fromlocal magnetic fields. however, theymay be compensated in precisely thesame way as is well understood in respect to ordinary magneticcompasses.

The direction controller 45 and the steering or deviation indicator 47are located in positions where they may be convenient to the pilot ornavigator of the craft. Electri- If such local fields do exist,

' ture is then perpendicular to a plane defined cal connection 67 and 67is made between the deviation indicator 47 and the generator brushes 77and 78, as previously described. The direction controller gear 40 andthe generator brush mounting gear 55 are mechanically connected by meansof chain and sprockets, or shafts and gearing, as illustrated, or by anyother suitable method of telemetric interconnection.

This interconnection is such that when theaircraft is headed north, andthe direction controller dial 44 shows North at the lubbers line 63,-theinductor plane of the armaby the axis of the armature and the directionof the earths flux, and hence the electric potential at the commutatorbrushes 77 and 7 8 is zero. It therefore follows that no current flowsto the deviation indicator 47 and a null or zero reading exists whichinforms the p1- lot that the craft is on the right course, 1. e.

on the course'shown by the direction controller dial 44.

In operation, the direction controller 45 has its compass dial 44 set toindicate the desired course at the index 63. The generator and itsbrushes being connected mechanically to orient about the journal pin 49through the same angle as the compass controller dial 44, is thereforeturned through that angle indicated in terms of direction by thecontroller dial, and doubtless the hand of the steering or deviationindicator 47 will 'deflect to right or left because the aircraft may notyet be on the desired course. The aircraft is then steered or guidedaround until the steering or deviation indicator 47 shows zero, at whichtime the heading of the craft will then be that directionindicated atthe lubbers line 63 on the controller compass dial 44, and will remainso as long as the pilot steers the craft to maintain zero on theelectric steering meter 47.

It will be apparent that a direction 180 ofi the indicated heading wouldalso produce a null reading on the steering indicator 47 because in thatevent the earths flux lines and the generator brushes are again in thatSince there is no current flowing while the direction of the craft isbeing indicated,.there is no magneto-motive force enerated, nodistortion of the earths fiel and consequently no error is' introducedfrom this source, which is important and contributes to the success ofmy invention.

While I have shown in Figures 1, 2 and 3 only one direction controllerand one steering or deviation indicator, connected to the generator, inpractice any number of controllers 45 and steering indicators 47 can beused with one inductor generator, thus permitting the .direction to bedetermined at several remotely located places, and enabling a boat orother craft to be equipped with any suitable'number of steering ordeviation indicating means 47. When used on large aircraft the electricsteering or deviation indicator 47 is placed where it is easily observedby the pilot, while in many cases, the direction controller 45 may beplaced conveniently to the navigator, perhaps at quite a distance awayfrom the steering or deviation indicator 47 and pilot.

As suggested, the navigator determines the course to be steered and thensets the course on the direction controller compass dial 44 by rotatingthe controller handle 99 and bringing the dial mark of direction to theindex 63. This adjustably turns the generator or brush mounting means 55and causes the steering or deviation indicator 47 to point to'the rightor tothe left of its zero. The pilot then changes the course'of theaircraft until the hand, of the indicator 47 comes back to zero, therebybringing the craft around to the heading the navigator has set on thecontroller compass dial 44.

It is seen that the compass system is so constructed that the navigatorat the direction controller 45 may be some distance from the electricsteering or deviation indicator 47, but he can signal the pilot, who isat the deviation indicator 47, the course the pilot must follow, and thenavigator does this by merely setting the desired course on thedirection controller compass dial 44, whereupon the pilot can read thecorresponding course on the similar compass dial 55 made on the gear 55in case the generator is visible to the pilot. The controller 45 andsteering and deviation indicator 47 may be placed side by side and readtogether and operated solely bythe pilot if desired.

I willnow describe another form of my invention. This is illustrated inFigures 5, 6, 7 and 8 wherein an armature 101'is carried on a shaft 104journaled in brackets 102 and 103 so that the generator is driven aboutthe normally horizontal axis 104. The arma ture may be driven bycompressed air or othersuitable means, and I have shown a turbine wheel116 carried on the armature, and a jet 117 for directing a stream of airagainst the turbine wheel;

' The brackets 102 and 103 are carried on a mounting base turntable orgear 105 which is rotatably carried by a generator base or frame 196 soas to be adjustably turned-about place not visible and furthermore thecontroller indicator 125 is suflicient.

A gyroscope 120 is mounted in the pendulum 109 for the purpose ofstabilizing or steadying the pendulum 109 and holding the brushes 107and 108 normally in one given position, as for example, horizontally.This gyroscope rotor 120 is journaled in a gyro frame 121 which is inturn pivoted in the pendulum 109 so that the gyro frame 121 may precessabout a normally vertical axis. The axis of precession of the gyro frame121 is restrained by a centralizing spring 124 so as to normally lie inthe plane of movement of the pendulum 109. 'Any tendency of the pendulum109 to swing is resisted by the gyroscope which stabilizes the brushesin a horizontal plane even though the entire generator unit itself mayroll or pitch due to the movement of the craft.

The gyroscope 120 is driven in any suitable manner, and I have shown itdriven by a stream of air which is directed against notches on thecircumference of the gyroscope by the jet 122. Air is conveyed to the etthrough aflexible tube 123.

Wires from the commutator brushes 107 and 108 are carried-to slip ringbrushes 111 and 112 which make contact with the slip rings 113 and 114.These slip rings are electrically connected to a galvanometer steeringor deviation indicator Figure 7 which may be similar to that shown in-Figure 3 and previously described.

The" direction controller 125 shown in Figure 6 performs the samefunctions in rotating the generator mounting gear 105 of Figure 5 as thedirection controller Figure 2 does in 'rotating' the turntable gear inFigure 1. In Figures 5 and 6, I have shown the generator mounting gear105 and controller compass dial indicator 125 connected together by asprocket chain 100 so that'they can be correspondingly and adjustablyturned together through the agency of a handle 126 fastened tothecompass dial means 125, so

that it may beeasily grasped by an operator. d;-

To illustrate the operation of the compas in this 'form of the invention(in Figures 5 through 8) I will first assume that the com-,

pass direction is as indicated by the-graduated compass controller card125, thatis, with the axis f-- of the generator in a N and S direction.As the armature 101 rotates, the

, cate controller is not disturbed, but the vehicle is coil 118 cuts thelines of flux of the earths magnetic field. In the position shown,however, the coil .is not effectively cutting any lines at the timeit'is connected, through the commutator bars 119, with the brushes 107and 108. The radial portions of the coil are, it is true, cutting linesat this time, but each in a direction'opposite to the other. There istherefore no potential between the brushes, and hence no effect upon thegalvanometer deviation indicator Figure 7, and therefore the heading ofthe craft is as shown on the direction controller index 127, namelynorth. I will now assume, however, that'the vehicle carrying the compassturns to the right, or clockwise. As the armature coil 118 rotates itnow cuts lines of flux and it is apparent that an electric potential isgenerated in the coil which gives to the brush 108 a positive potentialand to brush 107 a negative potential.

tial causes the hand to move to the right, in-

dicating. that the vehicle is headed to the and the position of thedirection controller 9 index 127 or the index 128 or both indexes thenshow the new direction in which the vehicle is headed.

' But, if on the other hand, it is desired to brin the vehicle back tothe heading indion the direction controller 125, said steered to theleft until the steering or deviation indicator Figure 7 returns to zeroor a null reading.

It will be seen that I have illustrated two alternate means foraccomplishing the purpose previously set forth, i. e. to so relate thearmature and brushes of the generator to each other andto the earthsfield, that the inductor plane of the armature is maintainedperpendicularto a lane defined by the armature axis and the direction ofthe earths flux. In the examples shown, the said means includesinstrumentalities to stabilize the brushes in a given position togetherwith a the vertical. However, it should also be understood that thealternate possibilities of .arran ement of armature, and brushes are notex austed by the two forms shown in my awings withinthe scope of thisinvention and the purposes above set forth, because 'the compassdirection controller functions per fectly to orient the brushes or thegenerator one or the other, whether or not they be stabilized. l

One oithe armatures shown is on a vertical axis, the other upon ahorizontal axis.

The connections in the gal- 'vanometer Figure 7 are such that thispoten- Any angle between the vertical and horizontal might have beenselected so long as the inductor plane of the generator is establishedor maintained in a given position. Obviously, every possible anglecannot be illustrated. In case the armature axis is inclined thegenerator is adjustably turned in be made under the principle of theinven- The compass controller dial 44 is 'tion.

azimuth through the angle necessary to bring the inductor plane of thearmature into the osition above defined. The compass then unctionsexactly the same as in the case of the two modifications which I haveillustrated. 1

Since the inductor plane of the armature in both forms ofthe inventionis maintained perpendicular .to a plane defined by the axis of thearmature and the direction of the earths flux, while the direction isbeing indicated, no error is introduced by the movements of the craftupon which the compass is mounted. Both sources'of error which have beenidentifiedwith previously proposed devices of remotely similar natureare therefore eliminated by my invention, and it fills a need felt for areliable compass especially on airplanes.

The compass controller as shown in Figures 2 or 6 is an importantelement in this inductor compass system and though above referred tomerely for an understanding of 44 is mounted upon and turns with thegear 40 but many modifications of construction may marked similar to anordinary compass card and 1s read 1n the same way.

. The compass controller 45 is connected by ear 40 and shaft means 99'or the like to t e inductor enerator, and the compass dla'l 44 and bruses 77 and 78 are designed to turn at the same angular rate so that thenavigator at the compass controller 45 may set the inductor generatorbrushes in the desired position by observing the compass dialindication, at the index 63.

For example, the navigator or the pilot knows, by setting a givendirection, say north, into the com ass dlal 44, that the generatorbrushes will esimilarly oriented to a 'zero potential position, i e., toa position where no potential is produced '(hencea' reading on thegalvanometer 47) when the craft shall have been steered to a northheading, whereupon the pilot may depend upon a'corr'ect north heading byaltering the crafts direction until a null indication is attained on thedeviation indicator 47 and by maintaining the craft on that heading.

Any suitable form of controller drive ma be provided, i. e., manual orpower, by whic the compass dial 44 and generator brushes aresimultaneously and uniformly oriented. A crank shaft means 99 isprovided both as a drive through a worm 39 to "the dial gear 40 and as atransmission means with pinion 43 to connect with the generator andbrush mounting gear 55. The gear ratios at the compass controllertransmission gearing 3940 and at the generator transmission gearing43-55 are the same so as to attain the same rate of turn for the'compasscontroller dial and generator brushes, and by reason of this arrangementthe angle of orient-ation of the brushes is directly shown at thecontrollefin terms of compass direction.

' Preferably the worm gears 39 and 43 are relatively smaller than thelarger gear means with which they engage and the pitch of the worms 39and 43 are so designed that many turns of the crank shaft means 99 arerequired to effect a 360 degree oriented adjustment of the compass dialand the generator brushes. Furthermore a finer and closer range orfractional degree setting of the compass dial 44 and generator brushes77 and 78 may be attained if a relatively low gear reduction be employedto turn the controller and brushes. The. gear reduction 39-40 and 4355also eliminates or greatly reduces errors in the 7 compass dial settingwhich would be otherwise introduced by reason of back lash in thelong'shafting 99' and its various connections. The shafting 99' enablesthe compass controller-and inductor generator to be remote- 1y installedon the craft if that be desired.

A worm and worm wheel type transmission 4355 are chosen for one form ofthe invention by which to turn the generator brush mounting means andhence orient the brushes because this type of transmission interlocksagainst accidental displacement and thus restrains the brushes againstmovement by v1- bration but instantly ermits a resetting of the brushesat the willof the operator.

It is obvious that the compass system is simple to install, that thegenerator may be placed in any convenient and eflicientlocation, that itis reliable and rugged in construction, that a fine compass setting ispossi-ble. The galvanometer or steering meter indicator 47 is sensitiveto the slightest devia-. tion from the heading on the com ass dial, andthe invention fills a need long elt.

What I claim 'is 1. An earth induotor compass system comprising; agenerator having an armature and commutator having current-collectingmeans,

including means for mounting the currentcollecting means for orientationthrough any desired angle about a normallyvertical axis; a controller,means interconnecting said controller with the generator to eifect theangular setting of the currentcollecting means, means to indicate theangle through which the current-collecting -means are oriented; and anelectric potential deviation indicator connected with thecurrent-collecting means.

2. An earth inductor compass system comprising; a generator having anarmature and commutator having current-collecting means, including meansfor mounting its current-collecting means for orientation through anydesired angle about a normally vertical axis; stabilizing means forestablishing the inductor plane of the armature in such position thatthe intersection of said plane with any plane per endicular to thearmature axis is normally orlzontal; a controller, means interconnectingsaid controller with the generator to effect the angular setting of thecurrentcollecting means, means to indicate the angle through which thecurrent-collecting means are-oriented; and an electric potentialdeviation indicator connected with the currentcollecting means. I

' 3. An earth inductor compass system comprising; a generator having anarmature, a commutator and brushes, and including means for mounting itsbrushes for orientation through any desired angle about a normallyvertical axis; stabilizing means for the 5 armature to establishits'axis substantially vertical; a c0ntrol1er,'means interconnecting itwith the generator to efl'ect the angular setting of the brushes, meansto indicate the angle through which the brushes are oriented; and anelectric potentialdeviation indicator connected with the brushes.

4. A compass comprising in combination, an electric generator includingan armature, a commutator-and brushes, a mounting base 5 supporting theenerator for adjustable turning movement a out a normally vertical axis,means for rotating the armature in the earths magnetic flux to produceelectric potential, a direction controller and connections foradjustably turning the mounting base and generator about said verticalaxis, and an electric deviation indicator connected with the commutatorbrushes.

5. A compass comprising in combination, a generator including anarmature, commutator and brushes, mounting means suppqrting thegenerator for ad ustable turning movement about a normally verticalaxis, driving means for rotating the armature 1n 0 the earths magneticflux toproduce electric potential, a direction controller andconnections for adjustably turning the mounting means and generatorabout said vertical axis,

an electric .potential responsive .steering indicator connected withsaid brushes, and an ing the generator for adjustable turning movementabout a normally vertical axis, driving means for rotating the armaturein the earths magnetic flux to produce electric potential, a directioncontroller and connections for adjustably turning the mountmg means andgenerator about said vertical axis, electric potential responsivesteering indicating means connected with said brushes, and a directionindicator carried on and turning with the mounting means to show itsadjusted position. l

7. A compass comprising in combination, a generator including anarmature. a commutator and current collecting brushes, mounting meanssupporting said brushes for adj ust able turning movement about anormally vertical axis, driving means for rotating said armature in theearths flux to produce electric potential, means for establishing theinductor plane of said armature perpendicular to a plane defined bythe'axis of said armature and the direction of the earths flux, saidlast named means including a direction controller for adj ustablyorienting the mounting means v and brushes togther with means forstabilizing'said brushes and a direction indicator operated by thedirection controller, and turning with the brushes, and a deviationindicator connected with the brushes.

8. A compass comprising in combination, a generator including anarmature and current collecting means, gear .means supporting thegenerator current-collecting means for orientation about a normallyvertical axis, driving means for rotating said armature in the earthsflux to produce electric potential, means for establishing the inductorplane of said armature perpendicular to a plane defined by the axis ofsaid armature and the direction of the earths flux; and said last namedmeans including a direction controller means for adjustably orientingsaid currentcollecting means together with gyroscopic means forstabilizing said current-collecting means; a direction indicatorconnected with and turned by thedirection controller to show the desiredheading, and an electric steering indicator connected with thecurrent-collecting means and showing a null reading when traveling onsaid desired heading.

9. A compass comprising in combination, a generator including anarmature, a commutator and current collecting brushes, mounting meanssupporting the brushes for adjustable turning movement about a normallyvertical axis, driving means for rotating the armature .in the earthsmagnetic flux to pro duce electric potential, a direction controller andconnect ons for turn-mg the mounting means and brushes about saidvertical ax1s on operation of said controller, an electric oten-- tialsteering indicator connected wit said generator brushes, and stabilizingmeans for establishing or maintaining the current 001- mutator andbrushes, mounting means sup porting the generator. for adjustableturning movement about a normally vertical axis,-

driving means for rotating the armature in the earths magnetic flux toproduce electric potential, a'direction controller and connections forturning the mounting means and generator about said. vertical axis, anelectric potential steering indicator connected with said brushes, andstabilizing means for establishing the generator in substantially agiven position in relation to a horizontal plane. 1

11. A compass comprising in combination, a generator including anarmature, a commutator 'and 'brushes, mounting means supporting thegenerator for adjustable turning movement about a normally verticalaxis, driving means for rotating the armature in the earths' magneticflux to produce electric potential, a direction controller for tumingthe mounting means and generator about said vertical axis, an electricpotential steering indicator connected withsaid brushes, and stabilizingmeans for establishing the axis of the generator in substantially avertical position.

12. A compass comprising in combination, a generator including anarmature, a com mutator and brushes, gyroscopic force producing means, auniversally pivoted means sustaining the generator whereby it inherentlystabilizes itself gyroscopically, mountmg means supporting the iiniversally pivoted means and generator for adjustable] turning movementabout a normally vertical axis, dr1v1ng means for rotating'the armaturein the earths magnetic'flux to produce electric potential, a directioncontroller for turning the mounting means about said vertical axis,

' and electric potential responsive means conas a steering indicator.

nected with said brushes and adapted for use 13. A compass compr sing incombination, an electric generator including an armature,

a commutator and brushes, a ,gimbal ring by 'i which the generator issustained and in which it inherently stabilizes itself gyros'copical--earth?s magnetic flux to produce electric potential, a directioncontroller for turning the a mounting gear supporting the afore-,

mounting gear with its stabilized generator about said vertical axis,and an'electric devi-v ation meter connected with the brushes and tiallya given position, an indicator of electric potential connected with thebrushes and used to indicate deviation, a direction controller includinga direction indicator adapted'to be set upon a desired course, and aconnection between the direction controller and mounting means, wherebymanual operation of said direction controller acts to adjustably turnthe generator brushes and the direction indicator. 4

15. A compass comprising in combination, anelectric generatorhavinganarmature, the axis of which is normally vertical, mounting meansadjustably turnable about a normally vertical axis and supporting thegenerator for universal movement, said vertical axis of both thegenerator armature and mounting means being normally coincidentlydisposed, stabilizing means maintaining the generator armature on asubstantially verti} cal axis irrespective of the relative position ofthe-axis of the mounting means, driving means for rotatingthe generatorarmature to produce electric potential, an electric devi'acard fromwhich course or heading is, read,

a rotary mounting device carrying the generator and adjustable about anormally vertical axis while stabilized as aforesaid, a

direction, controller and means connecting it with the compass card toturn said car'dto indicate'the desired course or heading, and meansconnecting the direction controller'- with the aforesaid rotary mountingdevice to orient the generator to a position in the earths field whereit discontinues the genera-i tion of potential thereby producing anullreading'on the aforesaid steering meter. when the vehicle isheadedas indicated on the compass card. v 17. A compass as-defined inclaim 16 characterized by a graduated direction indicat ing dial carriedon the rotary'mounting de v1ce. 18. A compass system com rising incombination, a direction contro ler, a steering meter, a frame, a base,a turntable pivoted for rotary movement relatively to said base, aconnection between the controller and turntable for orienting thelatter, a gimbal suspension interposed between said turntable and saidframe, a shaft journaled in said frame, an armature carried upon saidshaft, current collecting means interposed bemeans extendingtherethrough, a rotary mounting means carried on the ournal means, auniversally pivoted carrying means on the mounting means, a generatorsustained in the carrying means to inherently stabilize itself, meansdriving the generator to produce electrical potential and gyroscopicforce, a deviation indicator connected with the generator, and adirection controller and connections to adjustably turn the mountingmeans.

20. A compass comprising, a base, a journal carried thereby, a rotarymountingmeans s aced'from the base and adapted to turn a lit thejournal, 'a universally pivotedcarrying' means on the rotary mountingmeans, a generator. 'and driving means therefor sustained/in thecarrying means, means by which driving energy is transmitted from thebase to said driving means to drive the generator to produce electricpotential and gyroscopic force, a steering indicator connected with thenerator and operated by the otential, a 'rectioncontroller andconnect1on between said controller androtaryv mounting means toadjustably turn the mounting means.

21. A compass as defined in claim 20 wherein the journal extendingthrough the base is provided with a passage, the driving means includingan air driven member, and

an air connection between the passage and air driven' member. i 22. Anearth"inductor compass system comprising in combination; an inductorgenerator, including current collecting brushes,

'a commutator, and an armature; rotary 'mounting means supporting thegenerator brushesfor orientation about a normally ver- ;tic al axis;means for establishing the inductor plane of said armature in a givenposition perpendicular'to a plane defined by the axis of said armatureand the direction of the earths flux, including gyroscopic stabilizingmeans, a direction controller and a compass dial; an electric steeringindicator connected with the generator brushes and showing a nullreading when the inductor plane of the armature is maintained in theaforesaid given position; and the generator and direction generator andcontroller by which the rotary mounting means, the generator brushes,and the compass dial are simultaneously oriented at the same rate. a

23. An earth inductor compass comprising in combination; a generatorincluding an armature and current collecting brushes, a generator brushsupporting gear adapted to turn about a normally vertical axis andcarrying the brushes therewith, and a drive gear engaging the brushsupporting gear; a controller shaftand operating means therefor fixed tothe drive gear, a second drive gear fixed on the controller shaft inspaced relation from the first named drive gear, a compass directioncontroller gear driven by the second named drive gear, and a compassdial connected with and turned by the-compass direction controller gear;and the aforesaid gears comprising a slow motion drive by which thecompass dial and brushes are oriente'cl at a slower rate than thecontroller shaftturns, and having gear reduction ratios of-equal valueby which the,compass dial and brushes are uniformly turned at the sameangular rate; and a potential steering indicator connected with thebrushes.

-24. An earth inductor compass comprising, a generator having anarmature and current-collecting means, means for orienting the inductorplane ofgsaid generator about a normally vertical axis, means indicatingthe angle through which said inductor plane is oriented, and meansindicating the electric potential across said current-collecting means.I

25. An earth inductor compass comprising, a generator having an armatureand commutator brushes, meansfor orienting the inductor plane of saidgenerator about "a nor-' mally vertical axis, means indicating the anglethrough which said inductor plane is oriented, means indicating theelectric potential across said brushes, and means estabfishing theinductor plane in such relation to the armature; axisthat the line ofintersection of said inductor plane with any plane perpendicular tosaid'axi's -is"-norm,ally horizontal.

26.. An earth inductor. compass comprisin" "a enerator h'avin anarmature. and

commutator brushes, means for orienting the inductor plane of saidgenerator about a normally vertical axis, mean s'ineluding a comass dialand operatively connected with the rushes for indicating interms ofdirection the angle through which said inductor plane is oriented, andmeans indicating the electric potential across said brushes.

27. An earth inductor com ass comprising, a generator having an armatureand tor and commutator brushes, means for orienting. the inductor planeof said generator about a normally' vertical axis, means including acompass dial and operatively connected with the rushes for indicating interms of direction the angle through which said inductor plane isoriented, means indicating the electric pofirst named gear means, thecrank shaft aforesaid being operatively connected with both gear meansto turn the same, and means asv sociated withthe last named gear meansto mount a generator having current collecting brushes andfor orientingsaid brushes simultaneously with the turning movement of tential acrosssaid brushes, and means includethe compass dial.

ing a gyroscopic stabilizer for establishing the generator for universalpivotal movement, means for mounting said supporting means so as to beadjustable about a normally .vertical axis, a direction controller andconnections for making such adjustment, means for driving the armaturein the earths field, electric potential-responsive means adapted for useas a steerin v indicator and connect1ons therefrom to the generatorbrushes.

29. A compass comprising a generator having brushes and an armature,means-for universally mounting said armature,-a. stabilizing means forestablishing the axis of rotation of the armature substantiallyvertical, a deviation indicator operated by the generator, a controllerincluding an indicamature axis.

tor of direction capable of being set upon a desired course, anda-connection established between the controller and generator wherebymanual operation of the'controlle'r acts to orient the, generatorbrushes about the ar- 30. A controller for an earth inductor compasssystem, comprising in combination with generator current-collectingmeans and ro-.

tary mounting means therefor, of a driven member adapted to be connectedwith the ro- -tary mounting means, manually rotatable cmeans to operatethe driven member, a speed reducing connection between 831d. drivenmember and manually rotatable means, and

direction dial means operated by the driven.

member.

31. A controller for an earth inductor com pass system, comprising incombination with generator brushes and rotary mounting means therefor,of a driven member adapted to be connected with the rotary mountin/means, a manually rotatable shaft connecte "with the driven member,reducing gears between the shaft and driven member, and di- It rectiondial means'operated by the driven member. g

32. A directioncontroller for earthinductorcompasses comprising, a comass dial and lndex, gear means by which-the dial is turned,

a crank shaft to operate the gearmeans, an-

other'g ear means located remotely'from the rushes therefor, meanssupporting" means.

33. A compass controller comprising, in combination with-generatorbrushes and rotary mounting means carrying them for orientation, acompass dial, a gear cooperating therewith to orient the compass dial, acontroller shaft adapted to, be connected with the rotary mountingmeans, means to drive said shaft, and a reduction gearing connected withthe first named gear and with the shaft .nected with the rotary mountingmeans for orienting and setting the brushes; and means oonnectedwith.and turned by'the operating means to indicate, in' terms of direction,the

value of the angular displacement through. which the brushes areoriented and set.

35. A controller for an; earth inductor compass system comprising thecombination-withinductor generator brushes and rotary mounting meanscarrying them for complete orientation, of'operatmg means adapted to beconnected with the rotary mountlng means for orienting and setting thebrushes; and a compass dial connected with and turned by the operatingmeans to indicate, in terms of direction, the value vof the angulardisplacement through which thebrushes are oriented and set.

36. A controller for an earth inductor compass system comprising thecombination with inductor generator brushes and rotary mounting meanscarrying them for complete ori entation; and operating means including ashaft connection adapted to be operatively attached to the rotarymounting means fororienting and setting the brushes, and means fordrivmg the shaft; and a compass dial connected with the shaftandrot-ated there- .with simultaneously with the orientation of thebrushes. v

37. A controller for an earth inductor comass system comprising thecombination with inductor generator brushes and rotary mounting meanscarrying them for complete orientation; and operating means "includingpower transmitting means adapted tobe connected with the rotary mountingmeans for orienting and setting the brushes, and a crank for manuallyoperating the power transmitting means; and an indicator of directionconnected with the trunk, with the power transmitting means, and withthe rotary mounting means to measure the angle, in terms of direction;of the orientation of the brushes.

.In testimony whereof I aifix my signature at N. Y. city this 31st dayof January, 1922.

MORRIS M. TITTERINGTON.

